Validity of bond strength tests: A critical review-Part II

BACKGROUND: Macro-bond strength tests resulted in cohesive failures and overestimation of bond strengths. To reduce the flaws, micro-bond strength tests were introduced. They are the most commonly used bond-strength tests. OBJECTIVE: Thus the objective of this review is to critically review the reliability of micro-bond strength tests used to evaluate resin-tooth interface. DATA COLLECTION: Relevant articles published between January 1994 and July 2013 were collected from Pubmed database, Google scholar and hand searched journals of Conservative Dentistry, Endodontics and Dental materials. DATA SYNTHESIS: Variables that influence the test outcome are categorized into substrate related factors, factors related to specimen properties, specimen preparation and test methodology. Impact of these variables on the test outcome is critically analyzed. CONCLUSION: Micro-bond tests are more reliable than macro-bond tests. However, no standard format exists for reporting the bond strength tests which could lead to misinterpretation of the data and bonding abilities of adhesives.